Known tensioning and relaxing elements are, in many instances, used in tension ratchets. According to the European patent application EP-A1-0455085, a tension ratchet is known that permits the gradual release of a safety lock that prevents backward rotation by means of moving a tension lever to and fro.
In the known tension ratchets, both locking slides of the safety lock that prevents backward rotation are arranged one atop the other, next to the roll-up shaft on the base of the tension ratchet. In order to reduce the structural height of the ratchet, embodying the lock""s locking sides in a curved fashion is known, furthermore.
According to European patent application EP-A-1-0736698, it is known how to embody tension ratchets so that both locking slides are arranged so as to lie diametrically opposed to each other in relation to the locking wheel, and so that the locking slides"" direction of shift is essentially congruent with the mean longitudinal direction of the ratchet""s base.
The disadvantage to these tensioning/relaxing elements is that they all work according to the principle of engaging the slides in positive toothed, perforated gear wheels. For this reason, such tensioning/relaxing elements can be moved only in stages (tooth-hole size distance). The tensioning, and especially, the relaxation, generally occurs with a jerky lever motion by means of being moved to and fro. These jerky movements in the process of relaxation are associated with high mechanical stresses for the locking wheel.
It is the task of the invention to describe tensioning and relaxing elements in which the tensioning or relaxation occur continuously and variably.
According to the invention, this task is accomplished with tensioning and relaxing elements according to the wording of patent claim 1.